Supervisory system



March 1, 1932. c.- E. STEWART SUPERVISOR! SYSTEM Filed Sept. 19, 1928 L l- L LL;

TRANSMITTER FOR AC TUAT/NG ONE GROU OF 852 EC 70/98 TRA S/W TTER FOR O EPAT/NG IL L 0F 77/6 6515C TORS TRANS/WI 7" T57? F0 ACTJA TING 4A //V0/V/DUAL JELECTOR Inventor": Clyde E. Stewart,

His Abbor'heg.

Patented Mar. 1,1932

museums CLYDE E. STEWART, or DREXEL HILL, PENNSYLVANIA,-ASSIGNOR T GENERAL" ELECTRIC 'JODII 'ANY, A CORPORATION OF NEW YORK sUrnRvIsonY T SYSTEM Application filed September 19, 1928.. Serial No. 306,941.

My invention relates to remote supervisory systems,'and more particularly to means for remotely supervising'the operation of power switches or other movable devices.

, It has for its purpose to provide a method and means which are particularly adapted for use in connection with small power installations, or installationsin which switches are distributed about at dilferent locations,

either separate switches, or small groups of switches being located in each of the different locations, whereby the operation of said switches may be supervised from a central station. v q

I5 Briefly, in carrying my invention into effect, means are provided in connection w1th each switch whereby a common indicating device at the central station is operated in response to actuation, automatic, or otherwise,

in of any of the remote switches, together wlth -means whereby the operator at the central station bysending predetermined signals, as for-example, currentimpulses in code 00m? bination, toeach of the switches may produce additional actuation of the common indicating device at the central station only when a signal corresponding to the actuated switch has been transmitted from the central sta tion, In this -manner the operator at the central station may determine which or the remote switches operated. I

A further purpose of the inventionisto provide means whereby when two or more switcheshave been operated. simultaneously and the operator has, bythe means indicated, determined that a certain one oftwo or more switches has operated, he may afterwardsdeter nine which of the other switches has op- "M received upon a common indicating-device in the central station. I Another purpose of the invention is to providemeans whereby the: above results 'may be accomplished by the use of a single line, of pair of wires, extending fromthe central station to the locality of each of the remote switches. i j

Still another purpose of the invention is to provide means whereby the results indierated, notwithstanding'that theindicationis cated may be accomplished with a minimum of operations by .the operator.

Another purpose of the invention is to provide' means which are relatively inexpensive to install and maintain and which are simple in operation. I

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, both asto its organization and method of operation, to gether with further objects and advantages thereof, may best be'understood by reference to the following description taken in connec tionwith'theaccompanying drawing in which the single figure represents an embodiment of my invention. f 1 ,Referring to the drawing lhave repre I sented at A a central station from 'whicha' pair of conductors 1 extend tothe locality, or localities, of a plurality ofmovable devices such, for example, as that which I haveindicated as a switch 2. Associated' withqi'each of the movable devices or switches 2 is wa 'paratus' which'I have designated B on the Y drawing comprising. a plurality of switches 3, 3 and 3fwhich are mechanically c'onne'cted, or interlocked, withthe switch 2, and an induction coil 4 which is controlled thereby.. The switch 2'isshown in its normal,'or 30' closed, position and is adapted, upon actuation, to its off-normal, 'oropen', position to open the switch 3 and to closethe switch 3 and 3' for purposes presently to be described l m m i f The induction device 4 has a high frequen cy secondary winding'6 which'is connected through a cond'enserto the line 1. This device is also provided with aprimary or actuating winding? and an armature 8/ By actuation of the switch 2 to its off-normal position a circuit is completed'which extends from the negative side of a source of potential 9 through switch 3, normally closed contacts of relay 10, actuating winding 7 of theedevice 4, and stationary contact and armature'S to the positive side of the source'of potential 9. This circuit comprises ab'uzzer circuit for th'e coil 7 'which, by successively operating the armature 8, causes the'indu'ction coil 1 to supply high frequency current to the line 1 in a manner well known in the art. Also, upon opening of the switch 2 a circuit is completed extending from one side of asource of potential 11 through the switch 3 and actuating winding of relay 10 to the opposite side of the source 11, thereby causing energization of the relay 10. This relay may be of any suitable type which is adapted to open its contacts only after its actuating winding has been energized for a predetermined interval. W hen the contacts of this relay are opened the buzzer or actuating circuit of the induction coil is interrupted and the supply of high frequency current to the line is discontinued.

I It will thus be seen that upon actuation of any switch 2 to its oil normal position a high frequency current is supplied to the line 1 for a predetermined interval, as determined by the adjustment of the time delay device which is associated with relay 10.

Located in the central station A and connected across the line 1 is a suitable alternating current responsive indicating device 12 such, for example, as an induction howler or loud speaker. Of course, any visual indicating means may be used as Well. Thus, upon operation of switch 2 this howler will becaused to respond informing the operator at that station that one or more of the remote switches has been actuated to its off-normal position. Located also in the central station A are a plurality of signal sending, or impulse producing devices, whichare represented as disks 1 3, 13, 13". These devices are of well known construction and are provided with an actuating spring, not shown, and mechanism such that when the spring is wound by the operator the disks revolve through a complete revolution to produce, in cooperation with relays16 and 17, current impulses in the circuit 1' in suitable predetermined code combination; Line 1 at the central station extends through the contacts of relays 16 and 17 and a pairof choke coils 5 to a source of direct current potential 18. The relay 17 is of a type such that in one position it connects the source 18 to the line in a manner to produce current of a certain polarity in'the line and, upon actuation to the opposite position, it reverses the polarity of that current.

Each of the disks 13 is provided with a contact which is normally positioned in a notch in the rim of the disk such that it is out of engagement with the disk. Upon initiation of the rotation of the disk 13 the con tact 19 engages the disk and remains in engagement therewith throughout the complete revolution and until the disk 13 returns to its normal position. The disk 13 is provided with projections upon its periphery such that when the contact 19 engages these projections it is actuated into engagement with a second contact 20. The connections with the relays 16 and 17 are such that when the contact 19 engages the disk 13 the actuating winding of the relay 16 is energized and this relay closes its contacts. This circuit extends from the negative side of the source of potential 21 through contact 19, disk 13, and actuating winding of relay 16 to the opposite side of the source of potential 21. When the contact 19 engages the contact 20 a circuit is completed which extends from the negative side of the source of potential 21 through contacts 19 and 20, and actuating winding of the relay 17 to the opposite side of the source of potential 21. Thus, during a revolution of the disk the relay 16 is continuously energized and the relay 17 is alternately energized anddeenergized in accordance with the code combination determined by the projections on the disk 13. I

In this way current impulses of reverse polarity are transmitted through the line 1. For illustrative purposes, I have shown the disk 13 provided with an adjustable plate 22such that these current impulses may be divided into a pair of groups, each group having a predetermined number of impulses of reverse polarity. The disk 13 is so adjusted by means of the plate, 22 that a single group of impulses having any desired predetermined number of reversals may be transmitted. The disk 13 is provided with two plates 22" so adjusted that the transmitted impulses are divided into three groups;

Also comprised in the apparatus B, which is associated with each of the switches 2, is a selector switch 23 having an actuating winding 24* which is connected through a condenser to the line 1. This switch may be of any suitable construction but is of a type such that upon receipt of current impulses in code combination corresponding to the particular switch 2 its armature will engage a certain contact, and in response to a different code combination of impulses its armature will engage a difierent contact, or after actuation, will return to its initial position without engaging any contact. Preferably this switch is of a type shown in Patent No.

1,343,255, J. C. Field, issued July 15, 1920. Upon recepit from the line 1 by the selector 23 of a number of impulses in code combination corresponding to the particular switch which has been actuated, this selector'will engage its first contact and thereby complete .a circuit which extends from the negative side of the source of potential9 through switch 3 which is now closed, due to actuation of the switch to its off-normal position, armature and first contact of selector 23, contacts of relay 25, actuating winding of the induction coil 4, stationary contact and armature 8 to the positive side of the-source of potential 9.

Thus, it will be apparent that the contacts operated. f 1

of the selector 23 whichhas been actuated, as described, produce a short circuitabout the contacts of relay 10' and again energizethe induction coil, notwithstanding that operationof that device in response to operation of the switch 2,7has been interrupted by the relay 10. High frequency current will-then be erator of the station A, knowing; the code combinationwhich he'has transmitted and which has caused operation of'the indicating device 12, will then be informed as to which of the remoteswitches has operated.

Thus, upon operationof the device 12 in response to operation of any remote switch, the operator will proceed to operate the devices 13 at the central station until he receives an additional response from the device 12. This additional response will inform him that the switch corresponding to the code number which he last transmitted is the one that To obviate the fecessity of the operators dialing the number of every switch, the different remote switches are divided into groups, each grou'p'having a group number. The group divisions I have indicated 'by rectangles 26, 27 having conductors 28, 29 respectively leading therein, as to thedifierent devices B. Each of the individual'selector switches 23 in each group is adjustedto respond to the code combination of impulses corresponding to the group number, and also to a difieren't' combinationof impulsescorrespending to the individual number of the switch 2 with which the particular selector switch 23 is associated. 1 r

Thus, for example, let us suppose that there are 16 remote switches divided into groups of four. Upon receiving an indication from the [device 12 at the central station the operator will proceed-to dial the 1 group numbers of the different switches. Let us suppose that'he dialsthree group numbers a'ndreceives no response from the device 12. He is then informed that none of the switches inthe groups, the group numbers of which he has dialed, has been actuated. He then dials a fourth group number and receives a response from the device 12 indicating that one of the switches in this group has been actuated. He will then proceed to dial the individual numbers of the different switches in this last group. Upon dialing theiirst three individual numbers he receives no re-v sponse from the device 12. Upon dialing the fourth individualnumber he receives a respouse from the device 12 iniorminghim that it was the last of the six-teen switcheswhich operated. I r

When the operator dials 'agroup number and receives a responsefrom device. 12, he

doeslnot know-how many switchesin the group have operated. Also after he dials an individual number in the group and receives a response from device 12 hedoes not know whether any other switch, whose individual number hehas not dialed, has operated. ln acc'ordance with a feature of my invention, l provide an arrangement whereby the operator after he has dialed an individualnumber in a group and has re-' 1 ceivedaresponse from device 12, thereby indicating the operation of the corresponding switchin the group, may determine whether or not any other switch in the group has operated without dialing the individual numbers of all the otherswitches in the group. This result'is accomplished by providing an arrangement whereby induction device a of anoperated switch may be prevented from effecting the operation of the device 12 in response to the code of impulses which normally effects the operation thereof. In the particular embodiment. of my in vention shown in the drawing, this 1 result may be accomplished by dialing in any suit- 'ablem'anner, a code of impulses which will cause the'selectlve relay associated with a particular operated switch to be operated to its third contact position instead of its first contact position, therebyenergizing through an obvious circu t the left-hand winding of relay 25. This relay is of the position type such that upon energization of this winding 1' its armature is actuated from theposition shown in the drawingto the opposite position. The actuating winding 7 ofithe induc tion coil will then be deenergized. Operation of the other switches may thenbe -ascertained as described. VVith the relay 25 in the position opposite'to that shown in the drawing, when the switch 2 is returned to its relaywill be energized through a circuit including'the switch 3.'. This winding of the relay will return thefarmature to the *posiv tion-shown in the drawing, and the device 1s patent is employed, let us assume againlthat there are 16 switches divided into groups'of four.

' le'ctor switches will then be such that upon dialing of 17 impulses in a single group, as

by a disk adjusted as shownat 13, all of the v switches 23 will be operated to close their first contacts. If any remote switch is then in its oft-normal position, a response by thedevice 12 at the station A will be had. Thus the operator after. having determined that a particular switch has been actuated to'its The adjustment of the difierent senormal position, either manually or automaticall'y, the right-hand winding of this ofi-no'rmal position may advantageously dial the single group code number to determine whether any other switch in any. group two groups of impulses, as for example, dislr 13, every switch in the group to which that number pertains responds to close its first contacts, whereas the switches in other groups will not close their contacts but instead will return, after actuation to their initial position. It anyswitch in the groups, the group number of which has been dialed, is in its oil-normal position a response will be had from the device 12 at the station A. The individual numbers of the switches in each group will comprise three sets of impulses of which the first set will have the same number as the first set of the group number, and the sum of the impulses in the last two sets of the individual number will equal the numher in the second set of the group number; for example, in the group 7'10 the individual numb-ers will be 728 737, 746 and 'Z-37. Thus after the group in which a switch has operated is located the operator will dial the individual numbers until the individual switch is located. As pointed out above, after the operator has determined that a particular switch in a group has operated, the operator dials a code of impulses which causes the selective relay, associated with the operated switch, to cause the cor responding relay to occupy the position opposite to that shown in the drawin Tieretore when the selective relay 28 of the operated switch is subsequently moved to its first position in response to the group code, the selective relay doesnot effect the connection of the associated generator 11 to the line 1. The operator then dials the group number and if he receives a response from device 12 he knows that some other switch in the group has operated. He then dials the other individual code numbers or" the switches in the group until he receives an other response from the device 12. He repeats this cycle of operation until the dc vice 12 does not operate in response to the dialing of the group number.

While in the case shown in the drawing and described, I have represented an in duction coil and selector switch associated with each of the remote switches, it will of course be understood that since each oithe switches 23 is adapted to close any one of a plurality oi contacts in response to different code impulses, the system may readily be modified such that a single switch 23 and induction coil 4 may be associated with two or more of the switches 2 without departing from my invention.

' "While I have shown a single embodiment of my invention, it will of course be understood that I do not wish to be limited thereto since man modifications, both in the circuit arrangement and in the instrumentalities employed, may be made without departatrom the spirit and scope of my invention as set :Eorth in theappended claims.

Vlhat I claim as new and desire to secure by Letters Patent of the United States, is:

1. In a supervisory system, a line, a plurality of devices, means associated with each device for supplyinghigh frequency current to said line in response to the actuation of the device to a certain position, timing means associated with each device and controlled thereby for interrupting the supply of high frequency current to the line after the device has been insaidcertain position for a predetermined time, and means associated with each device and responsive to direct current impulses received from the line for causing additional high frequency current to be supplied to line when the device is in said certain position. i

2. In a supervisorysystem, a line, a-plurality of devices, means associated with each devicefor supplying high frequency current to saidline in response to the actuation of the device to a certain position, timing means associated with each device and controlled thereby for interrupting the supply of high frequency current to the line after the device has been in said certain position for a predetermined time, and means associated with each device and responsive to direct current impulses received from the line for additionally actuating the associated high frequency current supplying means without operating the device when the device is in said certain position. 7

8. In combination, a central station, aremote station including a plurality of devices, each of said devices having a normal position and an oil-normal position, a signal device in the central station common to all of the remote devices, means responsive to actuation of each of said remote devices from the normal position to an ofi-normal position for actuating said signal device for a predetermined time interval atter the actuation of theremote device, signal sending means at the central station, and means at the remote station responsive to a predetermined signal received from said central station for actuating said signal device subsequent to said time interval when said remote device is in its oilnormal position.

4-. ln-combinatmn, a central station, a remote station includin a. plurality of devices, a line joining said stations, means responsive to actuation of any or said devices for supplying high frequency current to said line,

ated device and to a predetermined code re ceived from the central station for causing said current supply means to supply current to said line to actuate saidsignal subsequent to operation of said time-controlled means.

5. In combination, a central station,a plurality of remote devices arranged in groups, a signal in said central station common to all of the remote devices, means responsive to actuation of any of said devices'to apredetermined position for effecting actuation of said signal for a predetermined tlme', code sending means in the central station, and code responslve means associated w1th each remote device, all of the code responsive means,

associated with said devices being responsive to a code common to the associated group and also to an individual code to effect the operation of said signal when the associated device is in said predetermined position and said code sending means is operated to trans mit either of said codes i 6. The combination, in a supervisory sys tem, a central station, a plurality of remote devices, a high frequency generator associated with each device having an energizing circuit, a pair of conductors extending from said central station to each of said generators, means responsive to operation of a device to a predetermined position for closing said energizing circuit, thereby to cause said generator to supply high frequency current to said conductors, a time delay relay controlled by the operation of said device for interrupting said circuit after a predetermined inter val, means in the central station for sending coded impulses over said conductors, selective means responsive to said coded impulses for closing said energizing circuit when the associated device is in said predetermined position,and an indicating device in said central station responsive to high frequency current received from said conductors.

' 7 Ina supervisory system, a plurality of devices, signal sending apparatus associated with each device and having an actuating circuit, means associated with each device for completing the actuating circuit of the associated signalsending apparatus when the device is automatically operated/tea certain position, means associated with each signal sending apparatus for interrupting; its respective actuating circuit a predetermined actuating circuits without operating the as} sociated device.

'8. In a supervisory system, a plurality'iof devices, a high frequency induction coill associated with each device and having an actuat-I ing circuit, means associated with each device for completing the associated actuating cir-' cuit in response to the operation of the device toa-certain' position, means associated with each device for interrupting the. associated actuating circuit a predetermined time interval after the operation of the device to saidcertain position, and remote controlled means. for subsequently completing any of said actuating circuits when the associated device is in said certain position without op:-'

eratingathe device. I V I 9. In a supervisory system, a plurality of devices, each having a normal and an oft? normal position, signal sendingapparatus as- I sociated with'each device and having an actuating circuit, means associated with each I Y device for completing the associated actuatmg circu t when the devlce is operated toits oft-normal position, means assoc ated w1th each signalsending apparatus for opening itsrespective actuating circuit a predeter- 'mined time after the completion thereof, a

normally closed switch associated with each signal-sendingapparatus, remote controlled 7 means for completing each actuating circuit through the associated switch when'the associated device is in its'ofi -normalposition, remote controlled means foropening each switch, and meansresponsive to the opera-v tion of a device to its normal position for cuit associated with each device, means associated with each group responsive to the code-individual to the group to control all;

of said circuits, said means'being responsiveto the individual codes of each device to control thesignal circuit of the respective de vice, means controlled-by said signal circuit to'operate said indicating device,and means associated with said remotedevice, forfpreventing operation of said "indicating device dependent upon the position of the respective remote device. 11. In combination, a central station in cluding an indicating device, a plurality of remote devices arranged in groups, each device being capable of assuming different pow sitions, each group andeach device in each group circuit associated with each device, means associated witheach group responsive to' the I code individual to the group to control all of said signal circuits, said'me'ans being responsive'to the individual-codes of each dehaving an individual code, a signal,

vice to control thesignal circuit of the re-:

spective device, mean s controlled by saidsignal circuit to operate said indicating de-' vice, and means associated with said remote device for preventing operation of said in dicating device dependent upon the position of the respective remote device, and additional means associated with each remote device for rendering said code responsive means unresponsive to control the corresponding signal circuit. v

12. In a supervisory system, a plurality of devices each or" which is capable of assuming either of two positions, a signal having an actuating circuit, a selector switch as sociated with each device and operable to a certain POSILIQI]. responsiveto two or more codes, connections whereby said actuating circuit is controlled by said switches when in said certain positionsthereby to cause operation of said signal, means for preventing operation of the signal dependent upon the positions of the two-position devices, and means responsive to the operation of a selector switch to a different position to prevent operation of said signal when the selector switch is subsequently operated to said certain position. v

18. In a supervisory system, a plurality of devices each of which is capable of assuming either of two positions, a signal having an actuating circuit, a selector switch associated with each device and operable to a certain position responsive to two or more codes, connections whereby said actuating circuit is controlled by said switches when in said certain positions thereby to cause operation of said signal, means for preventing operation of the signal dependent upon the positions of the two-position devices, a relay associated with each selector switch and having contacts connected to control said energizing circuit, means responsive to the operation of a selector to a predetermined difierent position for operating the associated relay to one position to control said actuating circuit and responsive to the operation of the associated device to operate the relay to another position.

In witness whereof, I have hereunto set my hand this 17th day of September, 1928.

CLYDE E. STEWART. 

